callback and forth with C

was messing around with C and blitzmax thought someone might find this useful...

callback.bmx

Strict
Import "./callb.c"

Extern "C"
	Function RegisterCallback ( fp:Byte Ptr )
	Function CallMe (a:Int)
End Extern

RegisterCallback( Test )
Local r:Int
r=callme(1)
Print "r="+r 

Function Test:Int( a:Int )
	Print "call back a="+a
	Return a+1
End Function

callb.c

int (*callback)(int *);

void RegisterCallback ( int *infunc )
{
	(int)callback = infunc;
}

int CallMe( int a){
	a=callback((int*)a);
	printf("in C a=%i\n",a);
	return a+1;
}

outputs

call back a=1
in C a=2
r=3